Beginning May 20, Domino's, the pizza delivery behemoth, will roll out a "tweet-to-order" system for U.S. customers. Domino's will be the first major player in the restaurant industry to use Twitter on an ongoing basis to place and complete an order.

Even wackier: Domino's regulars will be able to order by tweeting only the pizza emoji to @Dominos.

"It's the epitome of convenience," says CEO Patrick Doyle, in a phone interview. "We've got this down to a five-second exchange."

It's all about attracting busy, younger consumers. For Domino's it was a no-brainer, with upward of 50% of its sales already taking place digitally.

One analyst says it's savvy PR. Domino's will enjoy a "burst of publicity" as social media buzzes with the news, says Rebecca Lieb, digital advertising analyst at Altimeter Group. In the early going, she says, it also gives Domino's a competitive edge.

For Twitter, it's an evolution that the online social network is trying to make from a place to chat about or even advertise stuff to a place where folks can buy stuff. Several familiar retailers, including Old Navy and AMC Theaters, have tested selling items on Twitter via "buy now" buttons on tweets.

Twitter keeps looking for ways to grow and engage — and make money on — its more than 302 million monthly active users. Some 500 million tweets are sent every day.

"Our hope is that advertisers will keep innovating this way," says Twitter spokeswoman Genevieve Wong. "Twitter is the best platform to be creative like this."

Among others that have tested promotions of tweets for buying: Starbucks tried "tweet coffee to a friend," and the Miami Dolphins tried an in-stadium Tweet-a-Beer promotion where fans could order beer brought to their seats. But Domino's says this is a permanent option for ordering pizza going forward.

Over the past few years, Domino's has built a platform to vastly expand its technology, says Doyle. It has amassed a team of about 250 technology employees at its Ann Arbor, Mich., headquarters vs. about 50 tech employees just a decade ago, he says.

"We want to make it as easy as possible for people to order from us — and this is pretty darned easy," he says.

Among other tech-forward ways folks currently can order from Domino's: Samsung Smart TVs, Pebble and Android Wear smartwatches; Ford's SYNC AppLink, and the voice app "Dom."

Next? Doyle says that Domino's will continue to look at platforms "where people are spending time" such as Facebook and Instagram. "This certainly will not be our last platform."